A variety of container closures have been developed or proposed wherein an initial opening of a lid or a dispensing spout structure provides visual evidence of such an occurrence--even after the lid or spout has been subsequently closed. U.S. Pat. Nos. 4,487,324 and No. 4,941,592 disclose closures which incorporate a locking band or tab that is attached to either the lid or body of the closure with a plurality of frangible webs so as to initially retain the closure lid to the body in the closed position. To initially open the closure, the user must break the frangible webs by pushing or pulling on a tab or band.
U.S. Pat. No. 5,201,440 describes a container closure which includes a body for mounting on a container. The body defines a dispensing orifice. A lid is disposed on the body for being moved between open and closed positions relative to the dispensing orifice. A tamper-indicating member is provided as a unitary extension from the lid. A first frangible web connects the member to the lid. An anchor is connected with a second frangible web to another portion of the tamper-indicating member, and the anchor is retained by the closure body. The tamper-indicating member includes a graspable pull tab which can be pulled to completely sever the frangible webs connecting the tamper-indicating member to the lid and to the anchor. This permits the lid to be opened while providing evidence of tampering with the closure.
U.S. Pat. No. 5,875,907 discloses a closure for a container that has a body and a lid. The closure includes a tamper-indicating member connected to the body of the closure by an anchor member received in an anchor member-receiving aperture defined in the closure body. The tamper-indicating member is also connected along a frangible junction to the lid of the closure. A plug member extends from the tamper-indicating member and is receivable in a plug member-receiving aperture defined in the body. When the tamper-indicating member is depressed to force the plug member into the plug member-receiving aperture, the frangible junction is broken, and the tamper-indicating member is retained in its depressed position. This provides an indication that the closure may have been previously opened.
While the above-discussed closures can function well for the purposes for which they have been designed, it would be desirable to provide an improved tamper-evident closure which could be readily fabricated with certain types of lids or flow control elements and which, prior to the initial opening, could blend in with, or enhance, the cosmetic appearance of the closure. It would also be desirable for such a tamper-evident closure to be easily molded as one piece, including lid, body, and tamper-indicating portion, and to be easily deployed after molding to its tamper-indicating ready condition for eventual delivery to a user.
Further, it would be advantageous if such an improved closure could be initially opened relatively easily by the user. After such an improved closure has been initially opened and then closed, the closure should furnish a very clear indication that it has been previously opened. It would also be desirable to provide an improved tamper-evident closure design that includes a tamper-indicating member which, when altered during opening of the closure, would not result in the creation of a separate scrap piece that would require disposal.
The present invention provides an improved tamper-evident or tamper-indicating closure which can accommodate designs having the above-discussed benefits and features.